Alkali metal silicate-zinc hydroxychloride coating composition

摘要: An aqueous, alkaline, inorganic composition, comprising water-soluble alkali metal silicate and zinc hydroxychloride, is used to coat substrates normally infested by algae, such as silicate-containing building material, e.g., concrete roofing tiles, prevent or minimize algal infestation on said substrates, algae otherwise imparting a dark, unsightly appearance thereto.